HD depression, irritability, suicide risk, and VMAT2 interface (MEQ)

(i) Formulation and differentials. Leading cluster: major depression (biological symptoms, death wishes/burden beliefs) plus irritability/aggression (object throwing, short fuse) in manifest HD, with possible apathy overlap (sits unless prompted). Temporal link to tetrabenazine uptitration raises VMAT2-related dysphoria contribution.[1][5][8] Differentials: delirium (less likely without acute medical markers but consider aspiration/infection); pure apathy without depression; primary personality disorder (inadequate alone); substance use; medication toxicity; psychosis if paranoia emerges.[3][8]

(ii) Suicide risk. HD confers elevated suicidal ideation and behaviours; assess ideation, plan, intent, means (medication stockpile, weapons), past attempts, hopelessness, genetic 'curse' narrative, protective factors, and carer safety.[2][6] Acute steps: means restriction, increase supervision, crisis plan, consider hospital if intent/plan/high lethality or unsafe home, involve husband with consent/best-interest principles per local law (do not invent section numbers).[2][6]

(iii) Management. Joint neurology: review tetrabenazine dose/indication — TETRA-HD supports antichorea benefit but depression is a key adverse effect; reduce/stop if chorea allows or switch strategy.[5][7] Depression: start SSRI (e.g. sertraline 25–50 mg oral daily, titrate; or citalopram 10 mg oral daily with QTc/age caution); monitor activation and suicidality on initiation; sleep and psychological support.[3][7] Irritability: non-drug structure, carer education; SSRI often first drug step; if severe aggression persists, low-dose atypical (e.g. olanzapine 2.5–5 mg oral nocte or quetiapine 25 mg oral nocte) per expert algorithms, watch sedation/falls/rigidity.[3][4] For pure apathy components: OT/activation, not endless antidepressant stacking alone.[1][3]

(iv) Disposition. Multidisciplinary HD clinic follow-up (neurology, psychiatry, SLT for swallow, social work); genetics/family support for children at risk (no casual minor testing); advance care planning while capacity intact; carer support/respite; clear escalation for suicide or violence.[3][6][8]